Invisible grilles also cannot be cut using ordinary scissors. So for folks with young children, there is no need to worry about your tykes cutting through the grilles during an unsupervised crafting session.
The grilles can however be cut using a wire cutter, so be aware that invisible grilles shouldn’t be used for deterring whoever’s outside from coming in e.g. burglars, but rather to keep the occupants inside the home safe.
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